1. Field of the Invention
The present invention relates to a slide-bar device enabling a carrier such as a video recorder to move by arcs.
2. Description of the Related Art
When taking moving pictures, a camera needs to move in sync with the moving pictures. If the camera is held by hand, the problem of shaking and unsteadiness may be caused due to shake of the human body or lack of support to the hands, and thus the pictures taken are fuzzy and unclear. Therefore, a photographer may use a movable track structure as shown in FIG. 1. The track structure includes a left and a right fixed seat 1 corresponding to each other, two cylindrical slide bars 2 connected between the two fixed seats 1, and a base 3 assembled with the two slide bars 2. Two through holes 4 are provided on the bottom of the base 3, and the base 3 is assembled with the two slide bars 2 by means of the two through holes 4. The two fixed seats 1 are each pivotally connected to a sliding member 5, and a driving band 6 is wound on the two sliding members 5. The driving band 6 is connected and fixed to the base 3, and is enabled to rotate, thereby driving the base 3 to move along the two slide bars 2. A camera 7 is mounted on the base 3 and is movable with the base 3. Therefore, the problem that the pictures taken are fuzzy due to shake of the camera held by hand can be solved.
However, according to the existing track structure, the camera 7 can only move linearly, and cannot meet the requirements of the photographer. The main reason is that the pictures to be taken usually move by arcs, and the track structure only for linear displacement cannot be used for taking pictures in arc motion. Although arc-shaped tracks are available in the market, these existing arc-shaped tracks are fixed with a non-adjustable curvature, take a large space for storage, and have the disadvantage that the arc trajectory cannot be adjusted for taking changing pictures, so they still need to be improved.